Monday, January 27, 2020


Invasion Day protests held across nation and in London to challenge Australia Day date

Updated Sun at 6:16am
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VIDEO: Protest attendees talk about what January 26 means to them. (ABC News)
Rallies have been held across the country to oppose the celebration of Australia Day on January 26, which protesters say should be a day of mourning.

Key points:

  • Australia Day is considered a day of mourning by many Indigenous and non-Indigenous people
  • Demonstrators are calling for a rethink on how the day is celebrated
  • Protesters have gathered at a statue of Captain Cook in London
Invasion Day or Survival Day demonstrations have gained momentum in recent years and coincided with a push to move Australia Day to a date considered more inclusive.
January 26 marks the anniversary of the First Fleet's arrival in Port Jackson, New South Wales, which is regarded by many Indigenous and non-Indigenous Australians as the beginning of colonial oppression.
Tens of thousands of people gathered for Invasion Day rallies in the nation's capital cities including Melbourne and Sydney, where demonstrators congregated in a packed Hyde Park.
Many protesters wearing T-shirts featuring the Aboriginal flag, and carrying signs and placards, began Saturday's rally by watching a traditional smoking ceremony.
Speakers made a plea to stop black deaths in custody and increase Aboriginal ownership of land.
A march was then led by Aboriginal families who had lost loved ones in custody, alongside rugby league star Latrell Mitchell.
Mitchell, who was last year subjected to racial abuse, performed a short traditional dance at the protest, with South Sydney Rabbitohs team mate Cody Walker.
Mitchell said he was attending the rally to show solidarity with the Aboriginal community.
"For my daughter growing up, I just want her to know she can be a proud Indigenous woman when she grows up," he said.
"I want her to know how much her dad is doing good."
He urged the non-Indigenous community to learn about Aboriginal culture and history.
"Survival Day it's a celebration of our survival, our people. Obviously it's good to see people getting amongst it," Mitchell said.
"There's a lot to come and a lot to learn for people who don't understand."
Bundjalung elder Gwen Williams-Heckling travelled for 10 hours from Casino in NSW's north to attend the rally.
"January 26 is a bad day, a hurtful day, but we come here for solidarity," she said.
"Together we draw strength and celebrate our continuing culture despite our dispossession.
"We need a new day because we can never celebrate the day of invasion."

Huge rallies in Melbourne and Brisbane urging social justice

Tens of thousands of people turned out at another protest in Melbourne, with crowds chanting: "Always was, always will be Aboriginal land".
The Abolish Australia Day gathering outside Parliament House was organised by the Warriors of the Aboriginal Resistance.
The group called for an end to "systematic racism" and what it described as "racist and discriminatory" practices in law enforcement.
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Twitter: Joseph Dunstan tweet: Melbourne's Invasion Day rally march kicks off, heading down Bourke Street. @abcmelbourne
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It also demanded better protection of sacred cultural and environmental sites, which it said were being destroyed by mining companies.
In Brisbane's CBD protesters demonstrated in front of a statue of Queen Victoria before marching across the Victoria Bridge to Musgrave Park in West End.
Many children were present at the rally, and members of the crowd performed traditional dancing.
The demonstration was mostly peaceful, except for a minor scuffle in Queens Gardens in which a member of the crowd became angry and briefly took to the stage.
Police subdued the man and moved him on, before a succession of speakers continued the rally.
In regional Victoria, Ballarat held its first Survival Day smoking ceremony, with more than 1,000 people watching from the banks of Lake Wendouree at dawn.
Organiser Nikki Foy said she was spellbound as she watched droves of people arrive in the dark to the only early morning event of its kind outside metropolitan areas.
"I was expecting maybe 50 people … I'm absolutely overwhelmed by the attendance here," she said.
"It's a perfect start to what is a hard day, not only for the Aboriginal community but a lot of other people who have that understanding."
The council-backed event was hosted by the co-chair of Reconciliation Victoria, Ballarat-born Belinda Duarte, along with a number of long-time members of Ballarat's Aboriginal community.
A minute's silence was held as part of the ceremony, and some in the crowd openly wept as speakers addressed the history of colonial dispossession and read out the dates and locations of 19th century massacres.

London demonstrators gather at Captain Cook statue

This year, the protests have again gone global, with a group in London gathering at the statue of Captain Cook at The Mall, holding placards with such words as "no pride in genocide" and "sovereignty never ceded".
The group, London Australia Solidarity, said it stood "with First Nations people".
"London is the seat of empire and represents the beginning of colonialism," the group tweeted.
In Canberra, about 500 people joined a Survival Day march from the CBD over Commonwealth Bridge to the lawns of Parliament House.
Justine Brown from the United Ngunnawal Youth Council addressed the crowd, acknowledging the resilience of Indigenous people.
"This is the year that we come together as Australia's first people and non-Indigenous people, as Australians, as we should be," she said.
"We need a day where we feel safe, where non-Indigenous people feel safe to celebrate a nation that's great."
Large crowds gathered for an event commemorating the history of Aboriginal peoples in Darwin today.
There were dances and a smoking ceremony for those in attendance.
Organiser Jessie Bonson said the event was more a reconciliation event, rather than a rally or protest.
"This event is mainly about bringing our community together to open up a bit more of a discussion, to listen to our traditional owners — the Larrakia people — about how we should move forward together as a nation," she said.
Larrakia traditional owner June Mills delivered the Welcome to Country.
She said many people were still dealing with the effects of colonisation.
"You're not sorry when you continue down the line that you've been doing for 230 years. You're not sorry, you're not fooling anybody," she told the crowd.
In Hobart, protesters marched along Elizabeth Street, headed for the Parliament House lawn.
Tasmanian Aboriginal elder Jim Everett said he felt Australia was still a colony, and said more non-Indigenous people needed to speak out.
"We can't just run campaigns ourselves and get knocked back. We need your voices to start coming out," he said.
"Today's a day that I could cry. It's terrible.
"When you hear about the atrocities against the Aboriginal people in Australia, and the fact that the successive governments have not moved towards healing these divisions …"
A more subdued Survival Day event was organised at the Tandanya National Aboriginal Cultural Institute in Adelaide's CBD.
Institute chief executive Dennis Stokes said while many might regard the event as an occasion for shame, it was not necessarily meant to be confrontational.
Mr Stokes said it was instead focused on cross-cultural understanding.
"We don't see it as a protest, we see it as an inclusive event for the whole community, not just the Indigenous community, and we want to highlight Aboriginal and Torres Strait Islander culture," he said.
"We just show that we're here, we survived and our culture has survived as well.
"We want people to come down, especially non-Indigenous people, we want them to come down and have a look and see what we do."
Mr Stokes said Tandanya — which is described as Australia's oldest Aboriginal-owned and managed multi-arts centre — did not have a firm view on whether Australia Day should fall on another date.
"People have differences of opinion. Most people think that it's a day that should be changed but I think if we have a healthy debate about it we can figure out what to do," he said.


19th-century bee cells in a Panamanian cathedral shed light on human impact on ecosystems


19th-century bee cells in a Panamanian cathedral shed light on human impact on ecosystems
Locations of nest cell aggregations of Eufriesea surinamensis within the Cathedral in Casco Viejo, Panamá Credit: Paola Galgani-Barraza
Despite being "neotropical-forest-loving creatures," some orchid bees are known to tolerate habitats disturbed by human activity. However, little did the research team of Paola Galgani-Barraza (Smithsonian Tropical Research Institute) expect to find as many as 120 clusters of nearly two-centuries-old orchid bee nests built on the altarpiece of the Basilica Cathedral in Casco Viejo (Panamá). Their findings are published in the open-access Journal of Hymenoptera Research.
The discovery occurred after , completed in 2018 in preparation for the consecration of a new altar by Pope Francis, revealed the nests. Interestingly, many cells were covered with gold leaf and other golden material applied during an earlier restoration following an 1870 fire, thus aiding the reliable determination of the age of the clusters. The cells were dated to the years prior to 1871-1876.
The  that had once constructed the nests, was identified as the extremely secretive Eufriesea surinamensis. Females are known to build their nests distant from each other, making them very difficult to locate in the field. As a result, there is not much known about them: neither about the floral resources they collect for food, nor about the materials they use to build their nests, nor about the plants they pollinate.
However, by analysing the preserved pollen for the first time for this , the researchers successfully detected the presence of 48 plant species, representing 43 genera and 23 families. Hence, they concluded that late-nineteenth century Panama City was surrounded by a patchwork of tropical forests, sufficient to sustain nesting populations of what today is a forest-dwelling species of bee.
Not only did the scientists unveil important knowledge about the biology of  and the local floral diversity in the 19th century, but they also began to uncover key information about the functions of natural ecosystems and their component species, where bees play a crucial role as primary pollinators. Thus, the researchers hope to reveal how these environments are being modified by collective human behaviour, which is especially crucial with the rapidly changing environment that we witness today.

19th-century bee cells in a Panamanian cathedral shed light on human impact on ecosystems
Environs of the Eufriesea surinamensis nesting site in Casco Viejo, Panamá in 1875, as seen from the summit of Cerro Ancón. A white tower of the Cathedral where bees were nesting is visible in the distant background in the centre of the peninsula. Credit: Eadweard Muybridge, courtesy of the Smithsonian American Art Museum; gift of Mitchell and Nancy Steir.

More information: Paola Galgani-Barraza et al, Flower use by late nineteenth-century orchid bees (Eufriesea surinamensis, Hymenoptera, Apidae) nesting in the Catedral Basílica Santa María la Antigua de Panamá, Journal of Hymenoptera Research (2019). DOI: 10.3897/jhr.74.39191

Factors favor possible Austin mega-wildfire event

'When, not if it happens': Factors favor possible Austin mega-wildfire event


fire
Credit: CC0 Public Domain
All it will take for Central Texas to become the next area engulfed by catastrophic wildfires like those seen in Australia is a dry spring and summer, an errant flame and sustained winds.
Travis County  officials say the likelihood of such a mega-fire event is just a matter of time.
A recent report released by CoreLogic, an online property data service, ranked Austin fifth among  in the nation most at risk for wildfires. The only others in the country at a greater risk are in California, according to the study.
As the world watches and mourns over the wildfire devastation plaguing Australia, residents need only look out their window to see a similar landscape that Australians admired before the fires began.
Daniel Shaw, an Australian who has worked for the National Weather Service as a storm spotter, said his home country also built on the backs of preservation areas like Austin's wildlands to the west.
And, similar to residential growth near grassy areas east of Interstate 35, population growth in Australia has also pushed neighborhoods closer and closer to wild grasslands.
Shaw said if Austin's wildlands catch fire and embers blow into those grasslands, firefighters would struggle to extinguish the flames before another would start up nearby.
"If you've got fuel to burn and winds to drive it, then you're going to have a fast-running fire whether it's grasslands or bush," Shaw said.
Bob Nicks, president of the Austin firefighters union, said Austin's lack of sustained winds are now the only thing protecting Austin from a similar fate.
However, he said Austin's luck will eventually run dry.
"A 20 mph wind is devastating if it's sustained and blowing in one direction," Nicks said. "It's just a matter of when it happens, not if it happens."
Nicks said Central Texas frequently experiences two of the needed components for wildfires, dry conditions and triple-digit temperatures, from June through September during the summer wildfire season. However, sustained winds, the third factor that fuels the fires and pushes them forward in a singular direction, are less frequent.
If a fire was sparked in West Austin during hot, dry conditions when sustained winds were present, there would be no stopping it from destroying everything in its path, according to Nicks.
"When a fire reaches a certain size you cannot stop the progression forward," he said. "There is not enough water or personnel to put a dent on the head of that fire. You cannot stop it."
In 2011, as Central Texas vegetation withered during a historic drought, the most destructive wildfire in state history burned a total of 34,000 acres. The Bastrop Complex Fire destroyed 1,660 homes, killed two people and injured 12 others.
In Travis County, the 2011 wildfire season sparked 76 blazes and burned 9,835 acres, according to data collected by the Texas A&M Forest Service.
The 2011 season was the most devastating in the century for Texas, with a state-wide total of 30,896 fires and 9.94 million acres burned, the data said.
Even before the Bastrop fire, the forest service in 2008 tallied 175 fires that burned an average of 658 acres in Travis County alone. The next year, 50 fires burned an average of 95 acres in the county.
However, after 2011 the total number of fires and acres burned decreased significantly. The highest number of fires from 2011 through 2017 was in 2013 with 74 fires and 109 acres burned.
Randy Denzer, a vice president for the Austin Firefighters Association in Texas and the International Association of Firefighters Wildland Firefighting Task Force committee member, said the 2018 and 2019 fire seasons were also mild because of significant rainfall.
The combined total of acres burned for 2018 and 2019 was 107.
However, Denzer said, the increased moisture and lack of fires have allowed for vegetation to overgrow. Because of this, Central Texas is now at an extreme risk for wildfires, he said.
"The grasses are what carries the fires, and we have an overabundance now," Denzer said. "If we have a dry spring, we will be right back to where we were in 2011 by August of this year."
Although Central Texas received above-average rainfall in the first part of 2019, severe or extreme drought covered nearly the entire five-county Austin metro area in the fall, according to data from the U.S. Drought Monitor. Severe drought or extreme drought, which can include major crop or pasture losses and widespread water shortages or restrictions, are just below the U.S. Drought Monitor's worst condition, exceptional drought.
Extreme drought affected about 9.4% of Texas by October, including most of Hays and Travis counties.
Austin recorded 57 days last year when temperatures reached or surpassed 100 degrees, according to data collected at the city's main weather station at Camp Mabry. The highest temperature recorded was 105 degrees.
Denzer said climate change, which is causing drought conditions to persist throughout the state and temperatures to rise into the 100s more frequently, is putting Central Austin at a greater risk for fires.
"Climate change does have something to do with it," Denzer said. "Higher temperatures provide drier fuels, which creates better conditions for fires. Just a couple of degrees makes a difference.
"There is a bigger role, though, that is made by humans," he continued. "Everyone wants to live in an area with a pretty view. But now we can't have a fire burn in that area, so we have to stop it."
More than 53,000 residential properties in Austin are in the high to extreme risk zone for wildfires, according to the CoreLogic data. Cost of reconstruction in those areas would be approximately $16.35 billion, the data says.
Justice Jones, a wildfire mitigation officer for the Austin Fire Department, said where the fire occurs in Austin greatly affects the risks and intensity of the fire.
Jones said grass fires are seen daily during peak fire season in areas east of MoPac Boulevard (Loop 1) and Interstate 35. Those fires are often less intense because of less vegetation in the east, fire experts agree.
However, the west side of Travis County where residential areas intermingle with wooded areas are at risk of devastating, uncontrollable wildfires during hot, dry months because of dense vegetation.
"Right now Austin as a whole is at risk of wildfires," Denzer said. "West Austin though is at risk of 50-foot wildfires that are unstoppable. Any fires along unmanaged wildland areas, no matter how small they are, will be devastating."
Austin's push toward conservation has tied 30% of its land into preservation of natural areas. As Austin began to experience rapid population growth, however, construction of residential homes expanded closer to these preservation areas, which put that land at a greater risk of wildfires.
Carrie Stewart, Austin fire's wildfire division chief, said once a wildfire does start, its embers can blow over a mile and can easily ignite other wooded areas or homes.
"Those wildland fires can happen anywhere we have those large, open green spaces," Stewart said. "That's going to be all over the city of Austin where we have those risk areas."
The Texas A&M Forest Service created a risk assessment portal to show what parts of Travis County are at a greater risk with current weather conditions.
As of Tuesday, nearly every green space in or around Austin was listed as a high to very high risk of wildfires.
In California, an estimated 350,000 home and business owners were unable to find insurance agencies that would cover their properties following the states most deadly wildfire season in 2018, according to media reports.
Jerry Hagins, spokesperson for the Texas Department of Insurance, said insurance agencies base their coverage costs on long-term historical data, so the more wildfires that happen in a particular area the greater the risk of insurance prices skyrocketing or the insured being dropped altogether.
Hagins said because Austin has yet to experience consistent mega fire events over the past 10 to 20 years, he does not predict Travis County to suffer from the same insurance woes like California in the near future.
"I think California is pretty different from Texas in the frequency of wildfires and the severity of them," Hagins said. "But, we still do have that risk. We don't see rate changes after a single event because they are factored in for the long-term average."
However, Denzer disagreed.
"I think in the near future people will have issues finding affordable insurance if we don't do something about this," he said. "The CoreLogic data is for insurance investors. Insurance companies are going to start taking a look at this data and they are going to start looking into these risks."
However, there is something Austin officials can do to help prevent wildfires and decrease the risk of rising insurance costs, according to officials.
This year, Austin city council may vote on a $1.5 million plan that would require all new homes and businesses constructed near wildland areas to follow a wildland urban interface code, or WUI code.
The new code would mandate that all new structures in these areas be built with ignition-resistant materials to protect them from burning embers, which often sets buildings ablaze in a wildfire when they fall on wooden roofs, blow in through vents or lodge under boards.
Examples of ignition-resistant materials include double-paned glass windows and noncombustible screens over attic vents. Remodeled properties and new construction would have to comply.
Nicks said while any code is better than no code at all, the city council is only considering a portion of the full WUI code.
"The one they have up for council soon will have the least impact on risks today," Nicks said. "A properly written code would give the authority to mitigate fuels on certain property, which is a very big part of risk reduction. We're disappointed it doesn't include old construction."
Nicks said later this month he and his team will welcome  experts from California to re-visit the area and assess the risks and offer advice on how local officials can address a growing concern for wildfires in West Austin.
Denzer said he hopes the experts' opinions will push for the city council to consider adopting the full WUI code, which would hold landowners responsible for decreasing risks of wildfires on their own properties.
"I'm happy it's moving forward, but it does not do enough," Denzer said. "Adopting the full code is an investment, but it would reduce the risks of wildfires and of property insurance rates going up."

British carbon tax leads to 93% drop in coal-fired electricity

GOOD NEWS FOR THE PLANET 
BAD NEWS FOR ALBERTA'S KENNEY AND CANADA'S OTHER RIGHT WING PREMIERS

British carbon tax leads to 93% drop in coal-fired electricity

Credit: CC0 Public Domain
A tax on carbon dioxide emissions in Great Britain, introduced in 2013, has led to the proportion of electricity generated from coal falling from 40% to 3% over six years, according to research led by UCL.
British  generated from coal fell from 13.1 TWh (terawatt hours) in 2013 to 0.97 TWh in September 2019, and was replaced by other less emission-heavy forms of generation such as gas. The decline in coal generation accelerated substantially after the tax was increased in 2015.
In the report, 'The Value of International Electricity Trading', researchers from UCL and the University of Cambridge also showed that the tax—called Carbon Price Support—added on average £39 to British household electricity bills, collecting around £740m for the Treasury, in 2018.
Academics researched how the tax affected electricity flows to connected countries and interconnector (the large cables connecting the countries) revenue between 2015—when the tax was increased to £18 per tonne of  dioxide—and 2018. Following this increase, the share of coal-fired  fell from 28% in 2015 to 5% in 2018, reaching 3% by September 2019. Increased electricity imports from the continent reduced the price impact in the UK, and meant that some of the cost was paid through a slight increase in continental electricity  (mainly in France and the Netherlands).
Project lead Dr. Giorgio Castagneto Gissey (Bartlett Institute for Sustainable Resources, UCL) said: "Should EU countries also adopt a high carbon tax we would likely see huge carbon emission reductions throughout the Continent, as we've seen in Great Britain over the last few years."
Lead author, Professor David Newbery (University of Cambridge), said: "The Carbon Price Support provides a clear signal to our neighbours of its efficacy at reducing CO2 emissions."
The Carbon Price Support was introduced in England, Scotland and Wales at a rate of £4.94 per tonne of carbon dioxide-equivalent and is now capped at £18 until 2021.The tax is one part of the Total Carbon Price, which also includes the price of EU Emissions Trading System permits.
Report co-author Bowei Guo (University of Cambridge) said: "The Carbon Price Support has been instrumental in driving coal off the grid, but we show how it also creates distortions to cross-border trade, making a case for EU-wide adoption."
Professor Michael Grubb (Bartlett Institute for Sustainable Resources, UCL) said: "Great Britain's electricity transition is a monumental achievement of global interest, and has also demonstrated the power of an effective carbon price in lowering dependence on electricity generated from coal."
The overall report on electricity trading also covers the value of EU interconnectors to Great Britain, measures the efficiency of cross-border electricity trading and considers the value of post-Brexit decoupling from EU electricity markets.
Published today, the report annex focusing on the Carbon Price Support was produced by UCL to focus on the impact of the tax on British energy bills.
Renewables overtake hydrocarbons in UK electricity generation: study

More information: www.ucl.ac.uk/bartlett/sustain … m_20102019_final.pdf


Wild tomatoes resist devastating bacterial canker

Martha Sudermann, right, and Chris Peritore-Galve, graduate students in the lab of plant pathology and plant microbe biology professor Chris Smart, examine tomatoes growing in a greenhouse at Cornell AgriTech in Geneva. Credit: Allison Usavage/Cornell University
Many New York tomato growers are familiar with the scourge of bacterial canker—the wilted leaves and blistered fruit that can spoil an entire season's planting. For those whose livelihoods depend on tomatoes, this pathogen—Clavibacter michiganensis—is economically devastating.
In a new paper, Cornell researchers showed that wild tomato varieties are less affected by bacterial canker than traditionally cultivated varieties. The paper, "Characterizing Colonization Patterns of Clavibacter michiganensis During Infection of Tolerant Wild Solanum Species," published online in November in the journal Phytopathology.
Co-authors were Christine Smart, professor of plant pathology and plant-microbe biology in the College of Agriculture and Life Sciences; F. Christopher Peritore-Galve, a doctoral student in the Smart Lab; and Christine Miller, a 2018 Smart Lab undergraduate summer intern from North Carolina State University.
"Bacterial canker is pretty bad in New York," Peritore-Galve said, "but it's distributed worldwide, everywhere tomatoes are grown."
The pathogen causes wounding and is spread by wind-blown rain; if one tomato gets infected, it can spread from plant to plant.
"Bacterial canker certainly can cause the complete loss of a field of tomatoes, and we see outbreaks of the disease every year," Smart said. "Growers use disease management strategies, including spraying plants with copper-based products; however, once there is an outbreak it's difficult to control bacterial canker."
To combat diseases, plant pathologists and breeders often look for varieties that are resistant, but among tomatoes traditionally grown for market, there are none with genetic resistance to bacterial canker. So Peritore-Galve, Miller and Smart went back to the beginning.
Tomatoes are native to the Andes Mountains region of South America, where wild species have been free to evolve for thousands of years. Recently, plant breeders have identified wild tomatoes that seem to be less susceptible to bacterial canker and are resistant to other pathogens.
The team wanted to understand how bacteria spread and colonize in wild tomatoes versus cultivated ones. They zeroed in on the plants' vascular systems—specifically their xylem vessels.
Like individual veins in a human, xylem vessels transport water and nutrients from soil throughout the plant. The team found that in cultivated species, bacterial canker spreads everywhere, while in  the bacteria remain confined to certain xylem vessels without moving much into surrounding tissues.
"The wild tomatoes, for some reason, impede the ability of the bacteria to move up and down through the plants, which reduces symptoms—in this case, leaf wilt," Peritore-Galve said.
This is the first study ever confirming that  are susceptible to bacterial canker, though the infection is less severe than in cultivated varieties. But while a severe infection causes fewer symptoms in the wild plant, it can still cause lesions on the fruit.
Even so, a tomato variety with resistance to the bacteria could still be very helpful for tomato growers, said Chuck Bornt, vegetable specialist with Cornell Cooperative Extension's Eastern New York Commercial Horticulture program. Bornt works extensively with New York .
"Many times, it's not the fruit symptoms that cause the issue," Bornt said, "it's the wilting of the plants or the plugging of the xylem cells that cause the plant to lose foliage, which then exposes the fruit to sun scald and other issues. … nfected fruit are also an issue, but in my opinion it's these other issues that have more impact."
The 'Speck'-ter haunting New York tomato fields

More information: F. Christopher Peritore-Galve et al, Characterizing Colonization Patterns of Clavibacter michiganensis During Infection of Tolerant Wild Solanum Species, Phytopathology (2019). DOI: 10.1094/PHYTO-09-19-0329-R

Current model for storing nuclear waste is incomplete


Credit: CC0 Public Domain
The materials the United States and other countries plan to use to store high-level nuclear waste will likely degrade faster than anyone previously knew because of the way those materials interact, new research shows.
The findings, published today in the journal Nature Materials, show that  of  storage materials accelerates because of changes in the chemistry of the nuclear waste solution, and because of the way the materials interact with one another.
"This indicates that the  may not be sufficient to keep this waste safely stored," said Xiaolei Guo, lead author of the study and deputy director of Ohio State's Center for Performance and Design of Nuclear Waste Forms and Containers, part of the university's College of Engineering. "And it shows that we need to develop a new model for storing nuclear waste."
The team's research focused on storage materials for high-level nuclear waste—primarily defense waste, the legacy of past nuclear arms production. The waste is highly radioactive. While some types of the waste have half-lives of about 30 years, others—for example, plutonium—have a half-life that can be tens of thousands of years. The half-life of a radioactive element is the time needed for half of the material to decay.
The United States currently has no disposal site for that waste; according to the U.S. General Accountability Office, it is typically stored near the plants where it is produced. A permanent site has been proposed for Yucca Mountain in Nevada, though plans have stalled. Countries around the world have debated the best way to deal with nuclear waste; only one, Finland, has started construction on a long-term repository for high-level nuclear waste.
But the long-term plan for high-level defense waste disposal and storage around the globe is largely the same. It involves mixing the nuclear waste with other materials to form glass or ceramics, and then encasing those pieces of glass or ceramics—now radioactive—inside metallic canisters. The canisters then would be buried deep underground in a repository to isolate it.
In this study, the researchers found that when exposed to an aqueous environment, glass and ceramics interact with  to accelerate corrosion, especially of the glass and ceramic materials holding nuclear waste.
The study qualitatively measured the difference between accelerated corrosion and natural corrosion of the storage materials. Guo called it "severe."
"In the real-life scenario, the glass or ceramic waste forms would be in close contact with stainless  canisters. Under specific conditions, the corrosion of stainless steel will go crazy," he said. "It creates a super-aggressive environment that can corrode surrounding materials."
To analyze corrosion, the research team pressed glass or ceramic "waste forms"—the shapes into which nuclear waste is encapsulated—against stainless steel and immersed them in solutions for up to 30 days, under conditions that simulate those under Yucca Mountain, the proposed nuclear waste repository.
Those experiments showed that when glass and stainless steel were pressed against one another, stainless steel corrosion was "severe" and "localized," according to the study. The researchers also noted cracks and enhanced corrosion on the parts of the glass that had been in contact with stainless steel.
Part of the problem lies in the Periodic Table. Stainless steel is made primarily of iron mixed with other elements, including nickel and chromium. Iron has a chemical affinity for silicon, which is a key element of .
The experiments also showed that when ceramics—another potential holder for nuclear —were pressed against stainless steel under conditions that mimicked those beneath Yucca Mountain, both the ceramics and stainless steel corroded in a "severe localized" way.
Can citric acid be a green alternative to protecting steel?

More information: Self-accelerated corrosion of nuclear waste forms at material interfaces, Nature Materials (2020). DOI: 10.1038/s41563-019-0579-x , https://nature.com/articles/s41563-019-0579-x
Journal information: Nature Materials